Well why not combine?

I have been talking to the author of redux-react-firebase about combining, but we are not sure that the users of both want that at this point. Join us on the redux-firebase gitter if you haven't already since a ton of this type of discussion goes on there.

The author of redux-firebase has agreed to share the npm namespace! Currently the plan is to take the framework agnostic redux core logic of react-redux-firebase and place it into redux-firebase). Eventually react-redux-firebase and potentially other framework libraries can depend on that core (the new redux-firebase).

There isn't one, there is just a package-lock.json. npm v5.x.x adds support for a package-lock.json file which serves a similar purpose to a yarn.lock file. Instead of managing multiple lock files, the single package-lock.json contains exact version information for dependencies.